function serialize(mixed_value) {
  //  discuss at: http://phpjs.org/functions/serialize/
  // original by: Arpad Ray (mailto:arpad@php.net)
  // improved by: Dino
  // improved by: Le Torbi (http://www.letorbi.de/)
  // improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net/)
  // bugfixed by: Andrej Pavlovic
  // bugfixed by: Garagoth
  // bugfixed by: Russell Walker (http://www.nbill.co.uk/)
  // bugfixed by: Jamie Beck (http://www.terabit.ca/)
  // bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net/)
  // bugfixed by: Ben (http://benblume.co.uk/)
  // bugfixed by: Codestar (http://codestarlive.com/)
  //    input by: DtTvB (http://dt.in.th/2008-09-16.string-length-in-bytes.html)
  //    input by: Martin (http://www.erlenwiese.de/)
  //        note: We feel the main purpose of this function should be to ease the transport of data between php & js
  //        note: Aiming for PHP-compatibility, we have to translate objects to arrays
  //   example 1: serialize(['Kevin', 'van', 'Zonneveld']);
  //   returns 1: 'a:3:{i:0;s:5:"Kevin";i:1;s:3:"van";i:2;s:9:"Zonneveld";}'
  //   example 2: serialize({firstName: 'Kevin', midName: 'van', surName: 'Zonneveld'});
  //   returns 2: 'a:3:{s:9:"firstName";s:5:"Kevin";s:7:"midName";s:3:"van";s:7:"surName";s:9:"Zonneveld";}'

  var val, key, okey,
    ktype = '',
    vals = '',
    count = 0,
    _utf8Size = function(str) {
      var size = 0,
        i = 0,
        l = str.length,
        code = '';
      for (i = 0; i < l; i++) {
        code = str.charCodeAt(i);
        if (code < 0x0080) {
          size += 1;
        } else if (code < 0x0800) {
          size += 2;
        } else {
          size += 3;
        }
      }
      return size;
    },
    _getType = function(inp) {
      var match, key, cons, types, type = typeof inp;

      if (type === 'object' && !inp) {
        return 'null';
      }

      if (type === 'object') {
        if (!inp.constructor) {
          return 'object';
        }
        cons = inp.constructor.toString();
        match = cons.match(/(\w+)\(/);
        if (match) {
          cons = match[1].toLowerCase();
        }
        types = ['boolean', 'number', 'string', 'array'];
        for (key in types) {
          if (cons === types[key]) {
            type = types[key];
            break;
          }
        }
      }
      return type;
    },
    type = _getType(mixed_value);

  switch (type) {
  case 'function':
    val = '';
    break;
  case 'boolean':
    val = 'b:' + (mixed_value ? '1' : '0');
    break;
  case 'number':
    val = (Math.round(mixed_value) === mixed_value ? 'i' : 'd') + ':' + mixed_value;
    break;
  case 'string':
    val = 's:' + _utf8Size(mixed_value) + ':"' + mixed_value + '"';
    break;
  case 'array':
  case 'object':
    val = 'a';
    /*
        if (type === 'object') {
          var objname = mixed_value.constructor.toString().match(/(\w+)\(\)/);
          if (objname == undefined) {
            return;
          }
          objname[1] = this.serialize(objname[1]);
          val = 'O' + objname[1].substring(1, objname[1].length - 1);
        }
        */

    for (key in mixed_value) {
      if (mixed_value.hasOwnProperty(key)) {
        ktype = _getType(mixed_value[key]);
        if (ktype === 'function') {
          continue;
        }

        okey = (key.match(/^[0-9]+$/) ? parseInt(key, 10) : key);
        vals += this.serialize(okey) + this.serialize(mixed_value[key]);
        count++;
      }
    }
    val += ':' + count + ':{' + vals + '}';
    break;
  case 'undefined':
    // Fall-through
  default:
    // if the JS object has a property which contains a null value, the string cannot be unserialized by PHP
    val = 'N';
    break;
  }
  if (type !== 'object' && type !== 'array') {
    val += ';';
  }
  return val;
}
